The chemiluminescent compound, tetrakis(dimethylamino)ethylene which will hereinafter be referred to as TMAE, has been more extensively used than its analogs, was first reported by Pruett, et al., Journal of the American Chemical Society, 72, 3646 (1950). It is a clear and highly stable water insoluble liquid boiling at 200.degree. C. and freezing at 0.degree. C. Upon exposure to air or oxygen at room temperatures it undergoes an auto-oxidation which is accompanied by a chemiluminescence in the violet-blue-green region as per the following chemical reaction. ##STR1##
Further, U.S. Pat. No. 3,264,221 of Hilmer E. Winberg teaches improved sources of chemical light from new formulations containing TMAE, and that N, N, N', N'-tetramethylurea and N, N, N', N'-tetramethyloxamide are extremely effective agents in stopping the evolution of light during the oxidation of TMAE.
The practical application of TMAE and its analogs in the fabrication of a sandwich-like structure commonly referred to as a chemiluminescent panel marker or tape is more fully disclosed in U.S. Pat. No. 3,239,406, Chemiluminescent Structures and their Preparation, of Donald D. Coffman and Hilmer E. Winberg, dated 8 Mar. 1966.
Until now, it has not been possible to make useful, thermally stable, colored, chemiluminescent formulations of TMAE other than those formulations emitting the characteristic violet, blue, green colored light radiations of TMAE.
The problem of converting the violet-blue-green light of TMAE to a yellow, orange, red light has existed since the discovery of TMAE in 1950.
In the past this problem could not be satisfactorily overcome for the following reasons:
A. CHEMILUMINESCING TMAE produces approximately two photons of violet, blue, green light per the reaction of ten thousand molecules of TMAE with a stoichiometric quantity of oxygen;
B. CHEMILUMINESCING TMAE produces appreciably less than two photons of red, orange, yellow light per ten thousand molecules of TMAE reacting with oxygen.
c. when the light, generated as per a) and b) above, impinged on a selected substrate to which there had been applied a uniform layer of a conventional yellow, orange, red material or dye; the shorter (green, blue, violet), higher energy wavelengths were absorbed by the conventionally colored material and only the red, orange, yellow light emitted by the chemiluminescing TMAE were reflected by the material colored with a conventional non-fluorescent dye.
If the fluorescent rhodamine dyes and compositions of fluorescent rhodamine dyes were employed as color converters with TMAE containing formulations, the fluorescent rhodamine dyes faded upon storage. If the foregoing storage were heated, the fluorescent rhodamine dyes faded more rapidly.
The Methine and Polymethine Colouring Matters having the following identification and structure.sup.1 : FNT .sup.1 As described in Color Index.sup.2, American Association of Textile Chemists & Colorists, P.O. Box 12215 Research Triangle Park, North Carolina 27709 Volume 4, third edition, pages 4437 through 4440 FNT .sup.2 [Color Index. A numbered list of synthetic dyestuffs and inorganic pigments compiled by the Society of Dyers and Colourists (Yorkshire, England), which gives the scientific and commercial names, components, formulas, methods of preparation, discovers, literature references, and descriptions of properties and methods of application; 2d ed., 1958 (American Association of Textile Chemists and colorists, Lowell, Mass.) per page 170 of Hackh's Chemical Dictionary]
______________________________________ 48010Basic Dye (CI Constitution No.) ##STR2## ##STR3## Basic chloride of bis(1 methyl-3,3 dimethyl-2 indole)methane 48013CI Basic Violet 16 (bright bluish red) (CI Constitution No.) ##STR4## Basic chloride of 1-(1 methyl-3,3 dimethyl-2-indolyl)- 2[4(N,N-diethylaminobenzene)]ethylene [hereinafter 48013] 48035CI Basic Orange 21 (CI Constitution No.) ##STR5## Basic chloride of 1-(1 methyl-3,3 dimethyl-2 indolyl), 2(1,2 dimethyl-3-indolyl) ethylene, 48040CI basic Orange 22 (bright orange) (CI Constitution No.) ##STR6## Basic chloride of 1(1 methyl-3,3 dimethyl-2-indolyl), 2(1 methyl-2 benzo-3 indolyl) ethylene, 48070CI Basic Red 12 (bluish pink) (CI Constitution No.) ##STR7## Basic chloride of 1(1 methyl-3,3 dimethyl-2 indolyl), 3(1,3 dimethyl-2 indolyl) propyldiene 1,3, 48015CI Basic Red 13 (CI Constitution No.) ##STR8## Basic chloride of 1(1 methyl-3,3 dimethyl-2 indolyl), 2[4(N3 chloroethyl, N methyl amino) benzene] ethylene, CI Basic Red 14 Chemical Class: Cyanine Bright Red (fluorescent), and the flourescent rhodamine dyes having the following identification and structure: Rhodamine B, 45170B ##STR9## Rhodine 2 G, (SCI) 45165 ##STR10## Rhodamine 4 G, (IG) 45166 ##STR11## Rhodamin 6 G, 45160 ##STR12## do not react with or are not soluble in TMAE and have been found to be particularly well suited to practice this invention. ______________________________________
It is not known by the inventor whether other hemicyanine, methine, or polymethine fluorescent dyes or other rhodamine fluorescent dyes reacted with or were not soluble in TMAE and whether these other hemicyanine, methine or polymethine dyes or other rhodamine fluorescent dyes are well suited to practice this invention.